However, he will be succeeded by Stephen Kenny after the Euro 2020 campaign.
Republic of Ireland announced Mick McCarthy's return as manager on Sunday, with Terry Connor and Robbie Keane confirmed as his assistants.
However, the former Ipswich boss will be replaced by Stephen Kenny after the Euro 2020 campaign.
For now, Kenny, who recently stepped down from his role as manager of League of Ireland champions Dundalk, has been appointed coach of the Under-21 national team.
The head coach job of the Republic of Ireland became vacant after Martin O’Neill’s departure on Wednesday.
CONFIRMED | The FAI are delighted to announce that Mick McCarthy is the new Ireland Manager with Stephen Kenny with taking over as U21 Manager.— FAIreland ⚽️🇮🇪 (@FAIreland) 25 November 2018
Full story: https://t.co/Jwxe1142ow #COYBIG pic.twitter.com/aQdZub628Q
The 59-year-old McCarthy, formerly coach of Ireland from 1996 to 2002, said that he was "excited and honoured to be back with the Republic of Ireland".
He confirmed the news that Connor and the nation’s all-time leading goalscorer, Keane, will be his assistant coaches.
"I'm delighted to have Terry Connor, a trusted colleague and excellent coach, and Robbie Keane, one of the finest players who I had the pleasure of managing, helping me as assistant coaches," said McCarthy.
"I am looking forward to getting started and embracing this challenge to qualify for Euro 2020."
During his first spell at the Ireland helm, McCarthy oversaw 68 games and led the team to the round of 16 in the 2002 World Cup. At club level, he guided both Sunderland and Wolverhampton Wanderers to promotion to the English Premier League.